The term premature anti-fascist is mentioned in a post above. That was the derisive name stuck onto the members of the Lincoln Brigade when they returned to the U.S. A. after taking part in the Spanish Civil War in the 1930s. It was ostensibly the reason many of these people were hounded by the FBI to a greater or lesser degree for the rest of their lives. The term was used to trivialize all of their doings then.

Art Thieme